This chapter summarizes principles for understanding the human dynamics of safety. It pulls together 50 important principles that summarize the psychology of safety and lay the groundwork for building a Total Safety Culture. In a Total Safety Culture, people go beyond the call of duty for safety. This means they perform safe behaviors in various situations. Founded on research published in scientific journals, they enable profound understanding of the psychology of safety. Use them as guidelines to develop, implement, evaluate, and refine safety-improvement programs and make a positive difference in the safety of organization, community, or culture. In safety, the total recordable injury rate (TRIR) is the most popular evaluation number used to rank companies for safety rewards. The ultimate aim is to integrate behavior-based and person-based psychology so everyone participates in efforts to achieve a Total Safety Culture. In the ideal culture, everyone actively cares for the safety and health of others.